1. Field of the Invention
The present invention relates to an adapter for charging a rechargeable battery housed in a wireless earphone. In particular, the present invention relates to a wireless earphone charging adapter capable of charging the rechargeable battery of a wireless earphone using a power source of a main body in which the wireless earphone is employed.
2. Description of the Related Art
In general, conventional wireless earphones are used with devices that reproduce music or other audible signals. These reproducing devices include hand-held portable cassette players, MP3 players, among others. The wireless earphone receives sound signals wirelessly transmitted from a sound signal transmission unit of a main body and reproduces the sound signals into sound through a speaker provided in the wireless earphone. Such a wireless earphone comprises a receiver for receiving radio sound signals, and a battery for supplying electric power required for the receiver. Rechargeable batteries are generally used as the portable power source, which are capable of being charged and discharged many times.
Conventional wireless earphones are therefore provided with an exclusive charger for charging a rechargeable battery housed in the wireless earphone. The charger for a wireless earphone is typically formed as a DC power supply unit that supplies current of a predetermined rating required for charging the rechargeable battery when it is connected to a commercial power source. Therefore, the rechargeable battery of a wireless earphone can be charged only at a place where the commercial power source is provided.
When the conventional wireless earphone is used with a hand-held portable cassette player, or an MP3 player while commuting or when outdoors, no commercial power source is available. There is a problem in that because the rechargeable battery of the wireless earphone cannot be recharged after having been completely discharged, it is impossible to continuously use the portable cassette player or the MP3 player.